An object of absorbent articles, exemplified by infant's paper diapers, adult's paper diapers and sanitary napkins, is to prevent leakage of mainly bodily fluids such as urine and feces or the like, from the sides (side leakage) of the absorbent articles, and the absorbent articles are provided with leg gathers as indispensable structural components thereof.
Leg gathers are generally classified into two types. One type is an outer leg gather (also referred to as a “gusset gather.” Hereinafter, an outer leg gather will be referred to as an “OLG”) which is present on both the right and left side edges of the absorbent article body. The other is an inner leg gather (hereinafter, referred to as an “ILG”) which is provided inside the absorbent article and which sterically rises from both right and left sides of an absorber which is configured from a super absorbent polymer, pulp or the like.
Of these leg gathers, the ILG fulfills two functions in that, when the bodily fluid is excreted from a wearer, such bodily fluid that flows over the absorber surface is blocked by the side faces and at the same time the bodily fluid is prevented from transferring along the skin and leaking to the outside by allowing an end part (head part) of the ILG to make contact with the wearer's skin.
In order to fulfil such functions, ILGs conventionally have the following configurations:
(i) A leg part that blocks the bodily fluid on the side face and a head part that is connected from the leg part and that prevents the transfer and leakage by allowing the head part to make contact with the wearer's skin, are provided;
(ii) The head part is made of a stretchable material which allows it to have adhesion with the wearer's skin;
(iii) The leg part is configured by making use of a hydrophobic non-woven fabric which has leakage prevention properties for the material for preventing the permeation of bodily fluids.
(iv) The leg part is bonded to the absorber surface or the surface of a top sheet that covers the absorber surface and is configured to rise therefrom by using the bonded parts as a base end part; and
(v) The base end part of the leg part is bonded to near the right and left side edge parts of the absorber (or to the top sheet parts corresponding to the positions of the right and left side edge parts).
Such conventional absorbent articles, at the time of use, absorb the bodily fluid excreted onto an absorber, which is present between the right and left ILGs, in a manner of pressing and adhering such absorber against/to the wearer's skin.
However, in the absorbent articles having such conventional ILGs, the absorber and the ILGs, which are coupled thereto and are stiff, are pressed into a narrow crotch part and thus, irregular deformations such as kinks and folds or the like easily occur in the absorber, the absorption of bodily fluids is concentrated to part of the absorber and leakage easily occurs. In addition, an exchange to a new absorbent article is performed due to the generation of a feeling of discomfort arising from the above situation, and also, when used for an infant's diaper, due to the change of color of the so-called “pee indicator” prior to absorbing a predetermined amount of urine. Such pee indicator indicates the timing for changing diapers by, for example, changing the color when a predetermined amount of urine is excreted. Thus, currently, the absorbent articles having such conventional ILGs are not used according to the absorption capacity of the absorber. In fact, according to the statistics, in the case of current diapers for infants, the average value of the absorbed amount of bodily fluids in the absorbent article at the time of changing to an unused absorbent article is 50% or less of the absorption capability of the absorber.
Moreover, as described above, since, at the time of use of the absorbent article, the absorbent, which is present between the right and left ILGs, is pressed against and adhered to the wearer's skin, the urine and feces excreted onto the absorber will make contact with the wearer's skin for a prolonged period of time and skin troubles, such as diaper rash or the like, will be caused.
In order to solve such problems of conventional ILGs, it has been proposed to prevent kinks and folds or the like in the absorber by providing OLGs as well as by bringing the bonding positions of the ILGs to the absorber closer to the middle in the lateral direction (See Patent Document 1).